Characterisation and wear performance of plasma sprayed WC–Co coatings

AbstractIn the present paper, an evaluation is made of the effect of the characteristics of raw materials on the characteristics of plasma sprayed WC–Co coatings and their abrasion wear performance. The raw materials and the coatings were characterised using X-ray diffraction techniques and metallography. The coatings were subjected to a standard ASTM abrasion wear test and their relative performances were explained based on their characteristics. Mainly, it was found that the coating characteristics were affected by the particle size, chemistry, phase composition, and porosity of the powder, factors which are dependent on the method of manufacture of the powder. In turn, it was found that the coating characteristics such as phase composition, porosity, and carbide size affected the abrasion wear performance. In general, it appears that better abrasion wear resistance is provided by denser coatings, which have a very fine distribution of hard phases (such as η-carbides) and an absence of softer phases.MST/790